Allow DisplayDriverServer to write merge display drivers.

Adds option to server to allow a 'merge' driver that shares a display driver to write to.

Author: Linas Beresna

Changes

@@ -1,6 +1,10 @@
 10.5.x.x (relative to 10.5.11.0)
 ========
 
+Features
+--------
+
+- IECoreImage::DisplayDriverServer: Adds option to display server to client driver to write to the same display driver.
 
 
 10.5.11.0 (relative to 10.5.10.0)

include/IECoreImage/DisplayDriverServer.h

@@ -92,7 +92,6 @@ class IECOREIMAGE_API DisplayDriverServer : public IECore::RunTimeTyped
 		static const PortRange &registeredPortRange( const std::string &name );
 
 	private:
-
 		// Session class
 		// Takes care of one client connection.
 		class Session;

src/IECoreImage/DisplayDriverServer.cpp

@@ -53,6 +53,9 @@
 #include "boost/bind/bind.hpp"
 
 #include <thread>
+#include <map>
+#include <utility>
+#include <optional>
 
 #include <fcntl.h>
 #ifndef _MSC_VER
@@ -70,6 +73,14 @@ IE_CORE_DEFINERUNTIMETYPED( DisplayDriverServer );
 namespace
 {
 
+struct MergeDriverInfo
+{
+	DisplayDriverPtr mergeDriver = nullptr;
+	int mergeCount = 0;
+};
+
+using MergeMap = std::map<int, MergeDriverInfo>;
+
 /* Set the FD_CLOEXEC flag for the given socket descriptor, so that it will not exist on child processes.*/
 static void fixSocketFlags( int socketDesc )
 {
@@ -95,7 +106,7 @@ class DisplayDriverServer::Session : public RefCounted
 {
 	public:
 
-		Session( boost::asio::io_service& io_service );
+		Session( boost::asio::io_service& io_service, MergeMap& mergeMap );
 		~Session() override;
 
 		boost::asio::ip::tcp::socket& socket();
@@ -114,6 +125,8 @@ class DisplayDriverServer::Session : public RefCounted
 		DisplayDriverPtr m_displayDriver;
 		DisplayDriverServerHeader m_header;
 		CharVectorDataPtr m_buffer;
+		MergeMap& m_mergeMap;
+		std::optional<int> m_mergeId;
 };
 
 class DisplayDriverServer::PrivateData : public RefCounted
@@ -125,6 +138,7 @@ class DisplayDriverServer::PrivateData : public RefCounted
 		boost::asio::io_service m_service;
 		boost::asio::ip::tcp::acceptor m_acceptor;
 		std::thread m_thread;
+		MergeMap m_mergeMap;
 
 		PrivateData( DisplayDriverServer::Port portNumber ) :
 			m_service(),
@@ -196,7 +210,7 @@ DisplayDriverServer::DisplayDriverServer( DisplayDriverServer::Port portNumber )
 {
 	m_data = new DisplayDriverServer::PrivateData( portNumber );
 
-	DisplayDriverServer::SessionPtr newSession( new DisplayDriverServer::Session( m_data->m_service ) );
+	DisplayDriverServer::SessionPtr newSession( new DisplayDriverServer::Session( m_data->m_service, m_data->m_mergeMap ) );
 	m_data->m_acceptor.async_accept( newSession->socket(),
 			boost::bind( &DisplayDriverServer::handleAccept, this, newSession,
 			boost::asio::placeholders::error));
@@ -280,7 +294,7 @@ void DisplayDriverServer::handleAccept( DisplayDriverServer::SessionPtr session,
 {
 	if (!error)
 	{
-		DisplayDriverServer::SessionPtr newSession( new DisplayDriverServer::Session( m_data->m_service ) );
+		DisplayDriverServer::SessionPtr newSession( new DisplayDriverServer::Session( m_data->m_service, m_data->m_mergeMap ) );
 		m_data->m_acceptor.async_accept( newSession->socket(),
 				boost::bind( &DisplayDriverServer::handleAccept,  this, newSession,
 				boost::asio::placeholders::error));
@@ -292,8 +306,8 @@ void DisplayDriverServer::handleAccept( DisplayDriverServer::SessionPtr session,
  * DisplayDriverServer::Session functions
  */
 
-DisplayDriverServer::Session::Session( boost::asio::io_service& io_service ) :
-	m_socket( io_service ), m_displayDriver(nullptr), m_buffer( new CharVectorData( ) )
+DisplayDriverServer::Session::Session( boost::asio::io_service& io_service, MergeMap& mergeMap ) :
+	m_socket( io_service ), m_displayDriver(nullptr), m_buffer( new CharVectorData( ) ), m_mergeMap( mergeMap )
 {
 }
 
@@ -363,7 +377,19 @@ void DisplayDriverServer::Session::handleReadHeader( const boost::system::error_
 		{
 			try
 			{
-				m_displayDriver->imageClose();
+				if ( !m_mergeId.has_value() )
+				{
+					m_displayDriver->imageClose();
+				}
+				else
+				{
+					auto &m = m_mergeMap.at(m_mergeId.value()); // Error out if not found
+					if ( --m.mergeCount <= 0 )
+					{
+						m_mergeMap.erase(m_mergeId.value());
+						m_displayDriver->imageClose();
+					}
+				}
 			}
 			catch ( std::exception &e )
 			{
@@ -424,8 +450,31 @@ void DisplayDriverServer::Session::handleReadOpenParameters( const boost::system
 		const StringData *displayType = parameters->member<StringData>( "remoteDisplayType", true /* throw if missing */ );
 
 		// create a displayDriver using the factory function.
-		m_displayDriver = DisplayDriver::create( displayType->readable(), displayWindow->readable(), dataWindow->readable(), channelNames->readable(), parameters );
+		if ( !parameters->member<IntData>( "displayDriverServer:mergeId", false ) )
+		{
+			m_displayDriver = DisplayDriver::create( displayType->readable(), displayWindow->readable(), dataWindow->readable(), channelNames->readable(), parameters );
+		}
+		else
+		{
+			m_mergeId = parameters->member<IntData>( "displayDriverServer:mergeId", false /* throw if missing */ )->readable();
 
+			// Check if merge ID in map, if not then create display driver and session count pair with merge ID.
+			auto &m = m_mergeMap[m_mergeId.value()];
+			if ( !m.mergeDriver )
+			{
+				const IntData *sessionClientsData = parameters->member<IntData>( "displayDriverServer:mergeClients", true /* throw if missing */ );
+				m.mergeDriver= DisplayDriver::create(
+						displayType->readable(),
+						displayWindow->readable(),
+						displayWindow->readable(), // For merge we want dataWindow = displayWindow
+						channelNames->readable(),
+						parameters
+						);
+				m.mergeCount = sessionClientsData->readable();
+			}
+			// Merge ID is now in map, so load the display driver.
+			m_displayDriver = m.mergeDriver;
+		}
 		scanLineOrder = m_displayDriver->scanLineOrderOnly();
 		acceptsRepeatedData = m_displayDriver->acceptsRepeatedData();
 	}

test/IECoreImage/DisplayDriverServerTest.py

@@ -34,12 +34,20 @@
 
 import unittest
 import sys
+import os
+import imath
 
 import IECore
 import IECoreImage
 
 class DisplayDriverServerTest( unittest.TestCase ) :
 
+	def __prepareBuf( self, buf, width, offset, red, green, blue ):
+		for i in range( 0, width ):
+			buf[3*i] = blue[i+offset]
+			buf[3*i+1] = green[i+offset]
+			buf[3*i+2] = red[i+offset]
+
 	def testPortNumber( self ) :
 
 		s1 = IECoreImage.DisplayDriverServer( 1559 )
@@ -118,6 +126,63 @@ def testPortRangeRegistry( self ) :
 		s2 = IECoreImage.DisplayDriverServer()
 		self.assertEqual( s2.portNumber(), 45021 )
 
+	def testMergeMap( self ) :
+		server = IECoreImage.DisplayDriverServer( 45001 )
+
+		img = IECore.Reader.create( os.path.join( "test", "IECoreImage", "data", "tiff", "bluegreen_noise.400x300.tif" ) )()
+		self.assertEqual( img.keys(), [ 'B', 'G', 'R' ] )
+		red = img['R']
+		green = img['G']
+		blue = img['B']
+		width = img.dataWindow.max().x - img.dataWindow.min().x + 1
+
+		params = IECore.CompoundData()
+		params['displayHost'] = IECore.StringData('localhost')
+		params['displayPort'] = IECore.StringData( '45001' )
+		params['displayDriverServer:mergeId'] = IECore.IntData( 42 )
+		params['displayDriverServer:mergeClients'] = IECore.IntData( 2 )
+		params["remoteDisplayType"] = IECore.StringData( "ImageDisplayDriver" )
+		params["handle"] = IECore.StringData( "myHandle1" )
+
+		idd1 = IECoreImage.ClientDisplayDriver( img.displayWindow, img.dataWindow, list( img.channelNames() ), params )
+
+		params["handle"] = IECore.StringData( "myHandle2" )
+		idd2 = IECoreImage.ClientDisplayDriver( img.displayWindow, img.dataWindow, list( img.channelNames() ), params )
+
+		params['displayDriverServer:mergeId'] = IECore.IntData( 666 )
+		params['displayDriverServer:mergeClients'] = IECore.IntData( 1 )
+		params["handle"] = IECore.StringData( "myHandle3" )
+		idd3 = IECoreImage.ClientDisplayDriver( img.displayWindow, img.dataWindow, list( img.channelNames() ), params )
+
+		buf = IECore.FloatVectorData( width * 3 )
+		for i in range( 0, img.dataWindow.max().y - img.dataWindow.min().y + 1 ):
+			self.__prepareBuf( buf, width, i*width, red, green, blue )
+			idd1.imageData( imath.Box2i( imath.V2i( img.dataWindow.min().x, i + img.dataWindow.min().y ), imath.V2i( img.dataWindow.max().x, i + img.dataWindow.min().y) ), buf )
+			idd2.imageData( imath.Box2i( imath.V2i( img.dataWindow.min().x, i + img.dataWindow.min().y ), imath.V2i( img.dataWindow.max().x, i + img.dataWindow.min().y) ), buf )
+			idd3.imageData( imath.Box2i( imath.V2i( img.dataWindow.min().x, i + img.dataWindow.min().y ), imath.V2i( img.dataWindow.max().x, i + img.dataWindow.min().y) ), buf )
+
+		idd1.imageClose()
+		idd2.imageClose()
+		idd3.imageClose()
+
+		newImg = IECoreImage.ImageDisplayDriver.removeStoredImage( "myHandle1" )
+		newImg2 = IECoreImage.ImageDisplayDriver.removeStoredImage( "myHandle2" )
+		newImg3 = IECoreImage.ImageDisplayDriver.removeStoredImage( "myHandle3" )
+
+		# merge drivers share the same display driver - so second image should be none,
+		# as there is no image drivere associated with it.
+		self.assertIsNone( newImg2 )
+
+		# remove blindData for comparison
+		newImg.blindData().clear()
+		img.blindData().clear()
+		self.assertEqual( newImg, img )
+
+		newImg3.blindData().clear()
+		self.assertEqual( newImg3, img )
+
+		server = None
+
 if __name__ == "__main__":
 	unittest.main()